The strike in the troubled enclave of Cabinda underlines how a surprise attack can embarrass an overconfident or underprepared government, drawing international attention to an obscure struggle.

Before Friday's ambush, which killed two members of Togo's national soccer delegation and the driver of their team bus, the Front for the Liberation of the Enclave of Cabinda (FLEC) had been assumed to be in gradual decline, reduced to as few as 200 fighters.

Its long war with the central government was supposed to have ended in 2006. An Angolan government minister, who previously fought with FLEC, insisted it no longer existed as a fighting force.

Instead, what remains of the group -- which is fighting for greater control over huge oil revenues from the enclave -- was able to send a spectacular and lethal reminder of its existence.

Mark Schroeder, an Africa analyst with global intelligence firm Stratfor, said the killings had been an attack by FLEC "to say 'hey, we are still here'".